v3.26.1
Employee Benefits (Summary of Employee Benefit Plans Expenses) (Details) - CAD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Apr. 30, 2026
Apr. 30, 2025
Apr. 30, 2026
Apr. 30, 2025
Disclosure of defined benefit plans [line items]        
Defined Benefit Plan Expenses $ 248 $ 225 $ 589 $ 551
Principal Pension Plans [Member]        
Disclosure of defined benefit plans [line items]        
Service cost - benefits earned 68 69 137 138
Net interest cost (income) on net defined benefit liability (asset) (11) (13) (23) (25)
Past service cost 0 0 0 0
Defined benefit administrative expenses 3 2 (5) 5
Defined Benefit Plan Expenses 60 58 119 118
Principal post retirement benefit plan [Member]        
Disclosure of defined benefit plans [line items]        
Service cost - benefits earned 2 1 3 3
Net interest cost (income) on net defined benefit liability (asset) 4 4 8 8
Past service cost 0 0 0 0
Defined benefit administrative expenses 0 0 0 0
Defined Benefit Plan Expenses 6 5 11 11
Other pension and post retirement benefit plans [Member]        
Disclosure of defined benefit plans [line items]        
Service cost - benefits earned 5 5 10 10
Net interest cost (income) on net defined benefit liability (asset) 4 5 8 11
Past service cost 2 0 2 0
Defined benefit administrative expenses 1 2 (3) 3
Defined Benefit Plan Expenses $ 12 $ 12 $ 23 $ 24